Add retry logic and fallback to build on dev machines

[bweggersen]

If a fetch or put fails, it should quickly retry and then fall back to a regular build. The timeout should be short as most packages might not take that long to build.

Related, there should also be support for determining if the device is offline, and if so, it could look for a local cache, and if not it should simply build.

[bweggersen]

Maybe it's not a good idea to cover-up connectivity issues.